Friday, February 26th, 2016

Joe Tranquillo – Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Joe Tranquillo, Associate Professor of Biomedical & Electrical Engineering

Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Continue reading »

Friday, February 26th, 2016

James W. Baish – Kesler, Cristina T.; Pereira, Ethel R.; Cui, Cheryl H.; Nelson, Gregory M.; Masuck, David J.; Baish, James W.; and Padera, Timothy P. “Angiopoietin-4 Increases Permeability of Blood Vessels and Promotes Lymphatic Dilation.” FASEB Journal 29, no. 9 (2015) : 3668-3677.

James W. Baish, Professor of Biomedical Engineering

The angiopoietin (Ang) ligands are potential therapeutic targets for lymphatic related diseases, which include lymphedema and cancer. Ang-1 and Ang-2 functions are established, but those of Ang-4 are poorly understood. We used intravital fluorescence microscopy to characterize Ang-4 actions on T241 murine fibrosarcoma-associated vessels in mice. The diameters of lymphatic vessels draining Ang-4- or VEGF-C (positive control)expressing tumors increased to 123 and 135 mu m, respectively, and parental, mock-transduced (negative controls) and tumors expressing Ang-1 or Ang-2 remained at baseline (similar to 60 mu m). Ang-4 decreased human dermal lymphatic endothelial cell (LEC) monolayer permeability by 27% while increasing human dermal blood endothelial cell (BEC) monolayer permeability by 200%. In vivo, Ang-4 stimulated a 4.5-fold increase in tumor-associated blood vessel permeability compared with control when measured using intravital quantitative multiphoton microscopy. Ang-4 activated receptor signaling in both LECs and BECs, evidenced by tyrosine kinase with Ig and endothelial growth factor homology domains-2 (TIE2) receptor, protein kinase B, and Erk1,2 phosphorylation detectable by immunoblotting. These data suggest that Ang-4 actions are mediated through cell-type-specific networks and that lymphatic vessel dilation occurs secondarily to increased vascular leakage. Ang-4 also promoted survival of LECs. Thus, blocking Ang-4 may prune the draining lymphatic vasculature and decrease interstitial fluid pressure (IFP) by reducing vascular permeability.

Kesler, Cristina T.; Pereira, Ethel R.; Cui, Cheryl H.; Nelson, Gregory M.; Masuck, David J.; Baish, James W.; and Padera, Timothy P. “Angiopoietin-4 Increases Permeability of Blood Vessels and Promotes Lymphatic Dilation.” FASEB Journal 29, no. 9 (2015) : 3668-3677.

Continue reading »

Friday, February 26th, 2016

Eric Kennedy – Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Eric Kennedy, Associate Professor of Biomedical Engineering

Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Continue reading »

Friday, February 26th, 2016

Donna M. Ebenstein – Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Donna M. Ebenstein, Associate Professor of Biomedical Engineering

Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Continue reading »

Friday, February 26th, 2016

Donna M. Ebenstein – Tong, Kelly J. and Ebenstein, Donna M. “Comparison of Spherical and Flat Tips for Indentation of Hydrogels.” JOM 67, no. 4 (2015) : 713-719.

Donna M. Ebenstein, Associate Professor of Biomedical Engineering

Although both spherical and flat tips have been used in nanoindentation studies of soft biomaterials, care must be taken in selecting and validating a tip for a specific application. This article compares the moduli measured using spherical nanoindentation, flat tip (specifically, a flattened cone) nanoindentation, and unconfined compression testing of three polyacrylamide gels with nominal moduli between 10 kPa and 50 kPa. Although spherical indentation moduli were consistent with compression testing moduli and were independent of indentation depth, the flat tip results showed a significant increase in modulus with depth when analyzed using a flat punch model. Alternative methods are proposed to analyze the flat tip data to bring the flat tip results into alignment with the moduli measured using the other mechanical testing techniques.

Tong, Kelly J. and Ebenstein, Donna M. “Comparison of Spherical and Flat Tips for Indentation of Hydrogels.” JOM 67, no. 4 (2015) : 713-719.

Continue reading »

Friday, February 26th, 2016

Donna M. Ebenstein – Ebenstein, Donna M.; Calderon, Carlos; Troncoso, Omar P.; and Torres, Fernando G. “Characterization of Dermal Plates from Armored Catfish Pterygoplichthys pardalis Reveals Sandwich-Like Nanocomposite Structure.” Journal of the Mechanical Behavior of Biomedical Materials 45, (2015) : 175-182.

Donna M. Ebenstein, Associate Professor of Biomedical Engineering

Dermal plates from armored catfish are bony structures that cover their body. In this paper we characterized structural, chemical, and nanomechanical properties of the dermal plates from the Amazonian fish Pterygoplichthys pardalis. Analysis of the morphology of the plates using scanning electron microscopy (SEM) revealed that the dermal plates have a sandwich-like structure composed of an inner porous matrix surrounded by two external dense layers. This is different from the plywood-like laminated structure of elasmoid fish scales but similar to the structure of osteoderms found in the dermal armour of some reptiles and mammals. Chemical analysis performed using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results revealed similarities between the composition of P. pardalis plates and the elasmoid fish scales of Arapaima gigas. Reduced moduli of P. pardalis plates measured using nanoindentation were also consistent with reported values for A. gigas scales, but further revealed that the dermal plate is an anisotropic and heterogeneous material, similar to many other fish scales and osteoderms. It is postulated that the sandwich-like structure of the dermal plates provides a lightweight and tough protective layer.

Copyright 2015 Elsevier Ltd. All rights reserved.

Ebenstein, Donna M.; Calderon, Carlos; Troncoso, Omar P.; and Torres, Fernando G. “Characterization of Dermal Plates from Armored Catfish Pterygoplichthys pardalis Reveals Sandwich-Like Nanocomposite Structure.” Journal of the Mechanical Behavior of Biomedical Materials 45, (2015) : 175-182.

Continue reading »

Friday, February 26th, 2016

Daniel Cavanagh – Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Daniel Cavanagh, Associate Professor of Biomedical & Chemical Engineering

Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Continue reading »

Friday, February 26th, 2016

Kathleen Bieryla – Bieryla, Kathleen. “Xbox Kinect Training to Improve Clinical Measures of Balance in Older Adults: A Pilot Study.” Aging Clinical and Experimental Research (2015) : 1-7.

Kathleen Bieryla, Assistant Professor of Biomedical Engineering

Bieryla, Kathleen. “Xbox Kinect Training to Improve Clinical Measures of Balance in Older Adults: A Pilot Study.” Aging Clinical and Experimental Research (2015) : 1-7.

Continue reading »

Friday, February 26th, 2016

Kathleen Bieryla – Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Kathleen Bieryla, Assistant Professor of Biomedical Engineering

Tranquillo, Joe; Ebenstein, Donna; Kennedy, Eric; Bieryla, Kathleen; and Cavanagh, Dan. “Product Archaeology: Unearthing Business Decisions.” The Journal of Engineering Entrepreneurship 6, no. 1 (2015) : 22-36.

Continue reading »

Friday, February 26th, 2016

Kathleen Bieryla – Bieryla, Katie and Buffinton, Christine. “Effects of Age and Step Length on Joint Kinetics During Stepping Task.” Journal of Biomechanics 48, no. 10 (2015) : 1679-1686.

Kathleen Bieryla, Assistant Professor of Biomedical Engineering

Following a balance perturbation, a stepping response is commonly used to regain support, and the distance of the recovery step can vary. To date, no other studies have examined joint kinetics in young and old adults during increasing step distances, when participants are required to bring their rear foot forward. Therefore, the purpose of this study was to examine age-related differences in joint kinetics with increasing step distance. Twenty young and 20 old adults completed the study. Participants completed a step starting from double support, at an initial distance equal to the individual’s average step length. The distance was increased by 10% body height until an unsuccessful attempt. A one-way, repeated measures ANOVA was used to determine the effects of age on joint kinetics during the maximum step distance. A two-way, repeated measures, mixed model ANOVA was used to determine the effects of age, step distance, and their interaction on joint kinetics during the first three step distances for all participants. Young adults completed a significantly longer step than old adults. During the maximum step, in general, kinetic measures were greater in the young than in the old. As step distance increased, all but one kinetic measure increased for both young and old adults. This study has shown the ability to discriminate between young and old adults, and could potentially be used in the future to distinguish between fallers and non-fallers.

Copyright 2015 Elsevier Ltd. All rights reserved.

Bieryla, Katie and Buffinton, Christine. “Effects of Age and Step Length on Joint Kinetics During Stepping Task.” Journal of Biomechanics 48, no. 10 (2015) : 1679-1686.

Continue reading »

Friday, February 26th, 2016

Kathleen Bieryla – Buffinton, Christine; Buffinton, Elise M.; Bieryla, Kathleen; and Pratt, Jerry E. “Biomechanics of Step Initiation After Balance Recovery With Implications for Humanoid Robot Locomotion.” Journal of Biomechanical Engineering 138, no. 3 (2016 ).

Kathleen Bieryla, Assistant Professor of Biomedical Engineering

Buffinton, Christine; Buffinton, Elise M.; Bieryla, Kathleen; and Pratt, Jerry E. “Biomechanics of Step Initiation After Balance Recovery With Implications for Humanoid Robot Locomotion.” Journal of Biomechanical Engineering 138, no. 3 (2016 ).

Continue reading »

Friday, February 26th, 2016

James W. Baish – Stylianopoulos, Triantafyllos; Economides, Eva-Athena; Baish, James W.; Fukumura, Dai; and Jain, Rakesh K. “Towards Optimal Design of Cancer Nanomedicines: Multi-stage Nanoparticles for the Treatment of Solid Tumors.” Annals of Biomedical Engineering 43, no. 9 (2015) : 2291-2300.

James W. Baish, Professor of Biomedical Engineering

Conventional drug delivery systems for solid tumors are composed of a nano-carrier that releases its therapeutic load. These two-stage nanoparticles utilize the enhanced permeability and retention (EPR) effect to enable preferential delivery to tumor tissue. However, the size-dependency of the EPR, the limited penetration of nanoparticles into the tumor as well as the rapid binding of the particles or the released cytotoxic agents to cancer cells and stromal components inhibit the uniform distribution of the drug and the efficacy of the treatment. Here, we employ mathematical modeling to study the effect of particle size, drug release rate and binding affinity on the distribution and efficacy of nanoparticles to derive optimal design rules. Furthermore, we introduce a new multi-stage delivery system. The system consists of a 20-nm primary nanoparticle, which releases 5-nm secondary particles, which in turn release the chemotherapeutic drug. We found that tuning the drug release kinetics and binding affinities leads to improved delivery of the drug. Our results also indicate that multi-stage nanoparticles are superior over two-stage nano-carriers provided they have a faster drug release rate and for high binding affinity drugs. Furthermore, our results suggest that smaller nanoparticles achieve better treatment outcome.

Stylianopoulos, Triantafyllos; Economides, Eva-Athena; Baish, James W.; Fukumura, Dai; and Jain, Rakesh K. “Towards Optimal Design of Cancer Nanomedicines: Multi-stage Nanoparticles for the Treatment of Solid Tumors.” Annals of Biomedical Engineering 43, no. 9 (2015) : 2291-2300.

Continue reading »

Close

Places I've Been

The following links are virtual breadcrumbs marking the 12 most recent pages you have visited in Bucknell.edu. If you want to remember a specific page forever click the pin in the top right corner and we will be sure not to replace it. Close this message.